diff --git a/CHANGELOG b/CHANGELOG
index 6801e6ec4191190173c03669e96ae27c5b9c5fc3..30637327501a90bd9aade124bd6517a184a50c72 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,6 +1,8 @@
 minerva (15.0.0~alpha.0) stable; urgency=medium
   * Small improvement: when downloading a map results in too big file (>1MB)
     the content is compressed and returned as a zip file (#348)
+  * Small improvement: confirmation dialog when removing "general view"
+    overlays contain proper warning  (#809)
   * Bug fix: position of structural state is preserved on upload CellDesigner 
     file (#671)
 
diff --git a/frontend-js/src/main/js/gui/admin/EditProjectDialog.js b/frontend-js/src/main/js/gui/admin/EditProjectDialog.js
index 3097f39e91a271833cc3ec5850b0d2ca3375f7b9..0aab8b69b6f11ee5620d0335f9b0ba6b6a9aad7c 100644
--- a/frontend-js/src/main/js/gui/admin/EditProjectDialog.js
+++ b/frontend-js/src/main/js/gui/admin/EditProjectDialog.js
@@ -506,8 +506,14 @@ EditProjectDialog.prototype._createOverlayTable = function () {
     var button = this;
     var overlayId = parseInt($(button).attr("data"));
     var overlay = self._overlayById[overlayId];
+    var confirmationMessage = "Do you want to delete overlay: " + overlay.getName() + "?";
+    if (!overlay.getInputDataAvailable()) {
+      confirmationMessage += "<br/><span style='color:red;font-weight:bold'>Warning: This contains one of the map's " +
+        "diagrams and is required<br/>" +
+        "for map display. Removing it cannot be undone.</span>"
+    }
     return GuiConnector.showConfirmationDialog({
-      message: "Do you want to delete overlay: " + overlay.getName() + "?"
+      message: confirmationMessage
     }).then(function (confirmation) {
       if (confirmation) {
         $(button).attr("disabled", true);